Cassiopia at 12 weeks weighed 1.7 lbs and at 20 weeks she now weighs 2.3 lbs...she's currently pretty on target according to the chart. But who knows how much she will weight when she reaches 1 yr old. Since I've had her, she had only 1 growth spurt and the vet mentioned that once she hits 6 mths old, her growth rate will slow down a bit.
According to the Chart her adult weight would be 3 lbs. Not sure how true this is...as I've read a few comments from others where their yorkie had a similar weight at 12 weeks and ended up weighing around 5 lbs. In any case, as long she's healthy I guess it doesn't really matter what her adult weight will be.